Adenovirus-derived peptide–HLA complexes (AdV-peptide-HLA)

Adenovirus-derived peptide–HLA complexes are molecular assemblies consisting of short viral protein fragments, primarily derived from the highly conserved Hexon protein, bound within the peptide-binding groove of Human Leukocyte Antigen (HLA) molecules (UniProt P03277). These complexes are displayed on the surface of infected cells and serve as the essential recognition signal for the adaptive immune system, specifically for virus-specific T cells (VSTs). In immunocompromised patients, such as those undergoing hematopoietic stem cell transplantation (HSCT), the failure of the immune system to recognize these complexes can lead to fatal disseminated adenovirus infections (Leen et al., 2013, Biol Blood Marrow Transplant). Therapeutic interventions like Posoleucel (ALVR105) utilize donor-derived T cells that are primed to recognize these specific peptide-HLA targets, thereby restoring cellular immunity and clearing the viral infection (Allovir, 2023). The precision of this targeting is dependent on the patient's HLA genotype, making HLA matching a critical component of therapy. These complexes represent a cornerstone of modern immunotherapy for viral complications in transplant medicine.

Other names

Adenovirus peptide-MHC complexesAdV-pMHCAdenovirus antigen-HLA complexesAdV-HLA complexesAdenovirus-specific peptide-major histocompatibility complexes

The mechanism involves the recognition of specific adenovirus epitopes (typically from the Hexon protein) presented by HLA molecules on the surface of infected cells by the T-cell receptors (TCRs) of CD8+ or CD4+ T cells. This interaction triggers the activation of cytotoxic T lymphocytes (CTLs), leading to the release of perforin and granzymes that induce apoptosis in the infected host cell (Leen et al., 2006, Blood; Feuchtinger et al., 2004, Blood).